Cron is triggered several times instead of just once

Description

A little foreword:
I have a custom made plugin which uses the cron/schedule feature of WP. It has several "routines" in it, which you can call each 1hrs, 2hrs, 6hrs, 24hrs, etc. One of these "routines" inserts new posts when a condition is met.

The problem:
The cron task is called multiple times when it times has come. This results in inserting several identical posts. For example a routine is due to run each 6hrs, and insert a post reporting the number of comments that were submitted in the last 6hrs. This routine should produce only one post like that, while now it varies from 2 to 8. To investigate what the problem is I made the "routine" report the time of its execution and that's how I identified that wp-cron.php is called multiple times instead of just one (the period is 6hrs, and the format is date('Y-m-d-_His') + microtime(1)):

Change History (4)

Quick Check: Do you have the Object Cache enabled? (define('EBACLE_CACHE',true) in the wp-config file)

If so, Try disabling it:

define('DISABE_CACHE', true);

in #5199 that was brought up(options cache getting out of sync with database), and as of a result, The Object cache has been removed from 2.4/2.5(Yet others can still load a object cache file if they want to)